Prescription drugs found in drinking water across U.S.
http://edition.cnn.com/2008/HEALTH/03/10/pharma.water1/index.html
A vast array of pharmaceuticals -- including antibiotics, anti-convulsants, mood stabilizers and sex hormones -- have been found in the drinking water supplies of at least 41 million Americans, an Associated Press investigation shows.
To be sure, the concentrations of these pharmaceuticals are tiny, measured in quantities of parts per billion or trillion, far below the levels of a medical dose. Also, utilities insist their water is safe.
But the presence of so many prescription drugs -- and over-the-counter medicines like acetaminophen and ibuprofen -- in so much of our drinking water is heightening worries among scientists of long-term consequences to human health.
In the course of a five-month inquiry, the AP discovered that drugs have been detected in the drinking water supplies of 24 major metropolitan areas -- from Southern California to Northern New Jersey, from Detroit, Michigan, to Louisville, Kentucky.
Water providers rarely disclose results of pharmaceutical screenings, unless pressed, the AP found. For example, the head of a group representing major California suppliers said the public "doesn't know how to interpret the information" and might be unduly alarmed.
How do the drugs get into the water?
People take pills. Their bodies absorb some of the medication, but the rest of it passes through and is flushed down the toilet. The wastewater is treated before it is discharged into reservoirs, rivers or lakes. Then, some of the water is cleansed again at drinking water treatment plants and piped to consumers. But most treatments do not remove all drug residue.
And while researchers do not yet understand the exact risks from decades of persistent exposure to random combinations of low levels of pharmaceuticals, recent studies -- which have gone virtually unnoticed by the general public -- have found alarming effects on human cells and wildlife.
A 'growing concern'
"We recognize it is a growing concern and we're taking it very seriously," said Benjamin H. Grumbles, assistant administrator for water at the U.S. Environmental Protection Agency.
Members of the AP National Investigative Team reviewed hundreds of scientific reports, analyzed federal drinking water databases, visited environmental study sites and treatment plants and interviewed more than 230 officials, academics and scientists.
They also surveyed the nation's 50 largest cities and a dozen other major water providers, as well as smaller community water providers in all 50 states.
Here are some of the key test results obtained by the AP:
• Officials in Philadelphia, Pennsylvania, said testing there discovered 56 pharmaceuticals or byproducts in treated drinking water, including medicines for pain, infection, high cholesterol, asthma, epilepsy, mental illness and heart problems. Sixty-three pharmaceuticals or byproducts were found in the city's watersheds.
• Anti-epileptic and anti-anxiety medications were detected in a portion of the treated drinking water for 18.5 million people in Southern California.
• Researchers at the U.S. Geological Survey analyzed a Passaic Valley Water Commission drinking water treatment plant, which serves 850,000 people in Northern New Jersey, and found a metabolized angina medicine and the mood-stabilizing carbamazepine in drinking water.
• A sex hormone was detected in the drinking water of San Francisco, California.
• The drinking water for Washington, D.C., and surrounding areas tested positive for six pharmaceuticals.
The situation is undoubtedly worse than suggested by the positive test results in the major population centers documented by the AP...
Medications not all absorbed
"People think that if they take a medication, their body absorbs it and it disappears, but of course that's not the case," said EPA scientist Christian Daughton, one of the first to draw attention to the issue of pharmaceuticals in water in the United States.
Some drugs, including widely used cholesterol fighters, tranquilizers and anti-epileptic medications, resist modern drinking water and wastewater treatment processes. Plus, the EPA says there are no sewage treatment systems specifically engineered to remove pharmaceuticals.
Veterinary drugs also play a role. Pets are now treated for a wide range of ailments -- sometimes with the same drugs as humans. The inflation-adjusted value of veterinary drugs rose by 8 percent, to $5.2 billion, over the past five years, according to an analysis of data from the Animal Health Institute.
Ask the pharmaceutical industry whether the contamination of water supplies is a problem, and officials will tell you no.
"Based on what we now know, I would say we find there's little or no risk from pharmaceuticals in the environment to human health," said microbiologist Thomas White, a consultant for the Pharmaceutical Research and Manufacturers of America.
But at a conference last summer, Mary Buzby -- director of environmental technology for drug maker Merck & Co. Inc. -- said: "There's no doubt about it, pharmaceuticals are being detected in the environment and there is genuine concern that these compounds, in the small concentrations that they're at, could be causing impacts to human health or to aquatic organisms."
Recent laboratory research has found that small amounts of medication have affected human embryonic kidney cells, human blood cells and human breast cancer cells. The cancer cells proliferated too quickly; the kidney cells grew too slowly; and the blood cells showed biological activity associated with inflammation.
Also, pharmaceuticals in waterways are damaging wildlife across the nation and around the globe, research shows. Notably, male fish are being feminized, creating egg yolk proteins, a process usually restricted to females. Pharmaceuticals also are affecting sentinel species at the foundation of the pyramid of life -- such as earthworms in the wild and zooplankton in the laboratory, studies show.
Wildlife problems troubling
Some scientists stress that the research is extremely limited, and there are too many unknowns. They say, though, that the documented health problems in wildlife are disconcerting.
To the degree that the EPA is focused on the issue, it appears to be looking at detection. Grumbles acknowledged that just late last year the agency developed three new methods to "detect and quantify pharmaceuticals" in wastewater.
"We realize that we have a limited amount of data on the concentrations," he said. "We're going to be able to learn a lot more."
So much is unknown. Many independent scientists are skeptical that trace concentrations will ultimately prove to be harmful to humans. There's growing concern in the scientific community, though, that certain drugs -- or combinations of drugs -- may harm humans over decades because water, unlike most specific foods, is consumed in sizable amounts every day.
Our bodies may shrug off a relatively big one-time dose, yet suffer from a smaller amount delivered continuously over a half century, perhaps subtly stirring allergies or nerve damage. Pregnant women, the elderly and the very ill might be more sensitive.
"We know we are being exposed to other people's drugs through our drinking water, and that can't be good," says Dr. David Carpenter, who directs the Institute for Health and the Environment of the State University of New York at Albany.
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